A substrate used in a known display of the above description is formed from non-conductive material such as a circuit board, is relatively thin and has mounted on one substantially planar face thereof a plurality of spaced light emitting diodes (referred to hereinafter as LEDS) or groups of LEDS wherein the LEDS of each group are arranged in an alpha-numeric pattern. Where a number of alpha-numeric characters are to be displayed, for example nine digits, the width of the face of the substrate on which the LEDS are located, termed the "display face", is dictated in part by the amount of space requrired for the electrical conductor pattern. Additional displace face area is required when the cord is inserted into complementary card receiving and electrical contact means on the base to which the card is to be mounted. Due to the width of the display face of these known LED card displays, it was heretofore considered difficult to use display cards where close or dense packing of rows of alpha-numeric characters or rows of LED light sources was required. Indeed, even in single row character displays, the width of these known LED card displays has imposed certain design limitations due to the width of the display face.